Imagine as you are moving around your building at work, the fresh air you need to breathe follows you wherever you go. In this ideal building, energy efficiency would be maintained by not over conditioning areas that are vacant.
Ventilation system would need to be "smart" to accomplish this.
Fresh air makes people feel more comfortable and alert. The average person consumes three pounds of food, three liters of water, and 15,000 liters of air per day, but we don’t think about what we don’t see.
Indoor Air Quality
When thinking about indoor air quality, designing a system to provide fresh air throughout the facility should be the goal.
During the winter, air needs to be heated and humidified. In the summer, air needs to be cooled and dehumidified. Organic compounds that cause discomfort, so called TVOCs, allergens, pollen, and fine dust must be filtered out.
To maximize IAQ and help visualize it, a building owner or operator should rely on RESET certified sensors and reporting.
RESET is the only real-time, internationally recognized indoor air quality standard. An independent third party specialized in IAQ continuously verifies the measured values.
But let’s take a step back. Before undertaking any effort to improve the air quality in your building, it is critical to know what the current situation is.
Measure the humidity, CO2 and particulate matter, and even evaluate using their viral index. Use this as a baseline of measure after making your improvements.
It can be made possible by collecting data through sensors from different sectors in the building in real time, sending the data to a cloud based system that correlates the data and controls the energy needed on demand.
The current trend of more connected devices or "things," often referred to as IOT, the Internet of Things, empowers building owners.
This leads to the final consideration for a cloud-based data platform, reporting.
Whether you are in healthcare, education, or manufacturing, the ability to report on the air quality in your building will likely be necessary.
OSHA and city and state governments may require it in the future.
Having current and historical data with a system that can generate automatic reports is important. This not only helps regulation, but also demonstrates results of your investments in IAQ, and dedication to your employees’ health.
Building Connect software combines building automation with the known RESET global standard.
The Building Connect system is a cloud-based, real-time data platform that receives its data from sensors in the building, processes it in the cloud and passes on corresponding commands to the HVAC/IAQ equipment.
In addition to temperature, humidity, TVOC and fine dust, the sensors measure the CO2 content in the air that people exhale.
“600 parts per million or below are ideal values,” explained ebm-papst technical project manager Bernd Rohrscheid.
“From a value of 1,000 parts per million, the ability for a person to concentrate is already weakened. At 900 parts per million, our sensors start informing the fans in HVAC or IAQ systems to increase their air output accordingly. They ventilate until the level is back at 400 parts per million.”
Highly efficient fans that can measure air flow precisely and maintain it independently, as required per zone in the facility and are an integral part of the solution.
Precision airflow is a key part. This is where electrically commutated centrifugal fans are ideal for use. They are also small and quiet so they work well in any environment.
Are Air Purifiers the Solution?
Air purifiers are appliances that assist in the removal of pollutants from the air.
There are several types of purifiers using different technologies to either trap or destroy the particles.
The most common way to rid the air of pollutants is to capture them with a filter. HEPA filters and carbon filters are most common. HEPA filters are regulated and must capture 99.7% of all particulates larger than 0.3 microns, using their net of synthetic fibers.
They have also been shown to be effective against even smaller particles such as viruses.
Carbon filters are a little different. They are not efficient at capturing particulates, but rather gaseous pollutants, such as smoke, cooking fumes, VOCs, etc.
Most of the available air purifiers will use a combination of HEPA and carbon to filter everything.
Where filters trap particles, air purifiers will destroy or alter these particles.The two most common are UV and catalytic oxidation.
UV light inactivates microorganisms, molds, bacteria, and viruses in the air by altering the structure of their DNA, which stops them from multiplying.
Catalytic oxidation is a combination of light and a catalytic material which converts the pollutants into harmless components.
These are very effective at destroying viruses, bacteria, and mold, but not particles or gaseous components, like smoke. These types of purifiers are commonly used in conjunction with filters.
The Ideal Solution
There are two main types of air movers: axial and radial.
The most common style is an axial fan. The home window box fans we all have are a good example. They are flat or curved blades that simply blow air straight through.
These are great at moving large volumes of air in a wide open room, but if someone puts anything in the inlet or exhaust, the fans struggle. These would not be a good choice for moving air through a restrictive filter.
Radial fans are a bit different. The design of a radial fan allows the air to leave the fan in a direction that is at a right angle to the inlet. This design makes impellers much more efficient, as well as provides the ability to handle much higher restrictions or pressure drop; a perfect fit for a HEPA filter.
The most popular radial fan being used in air purifiers is a backward curved impeller.
This product offers a nice balance of features; low noise, compact size, high efficiency, and the ability to meet the restrictions created by these filters.
If fans are too noisy, operators will turn the speed down, which greatly reduces the effectiveness of the equipment. That is why the proper fan is so essential, especially in acoustic-sensitive areas such as hospitals, schools, and conference rooms.
Expansion of Choices
The heart of a fan is the motor.
AC and EC are two styles of fans that are common in the market.
AC motors have been around for well over a hundred years. They are good, cheap, and available in different sizes. They are good entry level technology, but do have drawbacks. Typically these motors are a little noisier and have limited speed control options.
Ebm-papst takes this technology and merges it with the external rotor design, which allows for a low profile AC solution for simpler applications.
EC motors are a technology pioneered by ebm-papst and an excellent choice for air purification. EC motors are a modern motor design. Although the motors are powered by the same AC voltage from the wall outlet, the motors internally are quite different.
EC motors offer more speed options, best in class ultra-high efficiency and lower noise too. This modern motor offers a speed control range two to three times larger than a traditional AC motor, meaning an air purifier using EC technology has different performance options.
As a result, the consumer has the perfect range of high performance to whisper quiet operation that consumes less energy.
To learn more about indoor air quality management, building optimization, or RESET, visit ebm-papst.